The parade and the truck with the video wall were contrived by producers though there’s no doubt they all like Mike, were happy to surprise him.
Jenny and Vinny said it best, he’s shown the growth they wish they showed themselves, to be better. That’s after a period when they didn’t like him, ghosted him.
Then Snookie’s appearance, again timed to surprise the rest of them, genuine reactions from Jenny and Mike.
It seems believable that if the show ended, several of them would be close and still spend time together.
Angelinas marriage, don’t really care, guess the producers